The kemo m172 usb bicycle charge controller usb mini b is the perfect device for environmentally concious bike enthusiasts using a dynamo attached to your bicycles wheel you can use the kemo m172 usb bicycle charge controller usb mini b to charge and power your bicycle lights as well as the operation of navigators pdas cell phones mp3 players etc on the bike if they have a mini usb power jack with generally conventional wiring the power to operate or charge the battery is provided by